South Coast Inland

A shift to warming temperatures and strengthening sunshine is drawing attention to surface instabilities on Tuesday.

Moderate - Timing or intensity of solar radiation is uncertain

Monday night: Mainly clear with some low cloud. Light variable winds. Tuesday: Sunny with some low cloud. Light northwest winds. Alpine high temperatures around -3 with a temperature inversion causing cooler temperatures at lower elevations.Wednesday: Sunny with some low cloud. Light northeast winds. Alpine high temperatures around -3 with a continuing temperature inversion causing cooler temperatures at lower elevations.Thursday: Sunny with some low cloud. Light variable winds. Alpine high temperatures around -3 under a lingering temperature inversion.

Two recent very large (size 3) avalanches were observed in the Joffre Lakes area on Saturday. These released from the high alpine northeast and northwest faces of Mt. Joffre and Mt. Matier, respectively. The evidence of the Mt. Matier slide features several 'step downs' as the slide progressively triggered deeper layers of the snowpack, all the way down to previous summer snow cover. Both slides likely released during last week's storm.Please submit any observations you have to the Mountain Information Network here.

Days of increasingly cool and clear weather have likely grown a new layer of feathery surface hoar crystals on the snow surface in most areas. Below the surface, it can be said with more certainty that the same cold has been transforming the storm snow from last week into a layer of faceted (sugary) snow. This layer of faceting storm snow increases in depth from about 5-10 cm at 1600-2000 metres, where it sits above a rain crust, to around 20-30 cm in the alpine above 2000 metres, where the crust may not be present. Here, the storm snow is suspected to be bonding well to a settled mid snowpack.Above 2000m, alpine snowpack depths are approaching 175 cm, although recent reports suggest about half these depths around treeline in the south of the region. A crust/facet interface can be found near the ground in the alpine, but this may again be most prevalent in the north of the region. Although little is known about the reactivity of this layer, recent observations in the north of the region show that it was reactive during last week's storm. It is thought that there is generally insufficient snow for avalanches below 1500 m.